300m级混凝土面板堆石坝变形可靠性分析

发布时间：2018-06-28 05:52

本文选题：混凝土面板堆石坝 + 改进一次二阶矩法　；参考：《北京交通大学》2014年硕士论文

【摘要】：目前我国混凝土面板堆石坝的发展正面临着从200m级坝高向300m级坝高发展的技术挑战,开展大坝变形可靠度分析是进行大坝安全分析和评价的有效手段与发展方向。本文首先对可靠度计算方法进行了研究,对最大熵法、改进一次二阶矩、响应面法、蒙特卡罗法以及Rosenblueth法等常见的结构可靠性分析方法的基本原理及其改进方法进行了介绍,研究了各种方法的优缺点和适用范围,提出了控制积分区间长度、采用遗传算法和matlab fsolve函数相结合的方程组求解方法,提高了最大熵法求解成功率。本文旨在提出一套混凝土面板堆石坝风险分析分析的方法并对坝体变形可靠性进行研究。本文首先在陈祖煜院士改进一次二阶矩法的基础上,将一次二阶矩法与数值计算程序有机结合,将改进一次二阶矩法引入复杂结构可靠性分析领域,与目前常用的响应面法相比,该方法具有收敛性好、计算精度高、计算效率高的优点。然后本文中通过将改进一次二阶矩法与Rosenblueth法相结合提出了一套评价混凝土面板堆石坝风险水平的方法,并对一座300m级典型混凝土面板堆石坝坝截面竖向沉降变形和挠曲变形的变形特性进行了分析研究,研究表明邓肯-张E-B模型参数(?)0、Rf、n、K、(?)、m、Kb、Kur,(其中(?)0、(?)为材料强度参数,n、K为切线模量试验常数,m、Kb为体积模量试验常数,Rf为破坏比,Kur为卸载-再加载模量试验常数),对坝体变形的影响较为复杂,与参数值、参考点位置、变形类别都有关系,对于水平变形敏感性按照(/)0、Rf、n、K、(?)、m、Kb、Kur的顺序逐渐减小,对于竖向沉降不同位置处参数敏感性排序不同,(/)0、Kb岛、m、Rf是影响竖向变形的主要因素。本文最后还对竣工期和蓄水期300m级混凝土面板堆石坝坝体沉降变形可靠指标以及面板挠曲变形可靠指标对(/)0、Rf、K、(?)、Kb这五个参数的变异系数进行了敏感性分析,通过分析计算发现Kb、(?)0的变异系数对沉降变形可靠指标的影响远大于其它三个因素,而(?)O、Rf变异系数对沉降变形可靠指标影响很小,而对于面板挠曲变形可靠指标其敏感性按照K、(?)0、Rf、Kb、(?)的顺序递减,K、(?)0的变异性是影响面板挠曲变形可靠指标的主要因素。
[Abstract]:At present, the development of concrete face rockfill dam in China is facing the technical challenge from 200m dam height to 300m dam height. The reliability analysis of dam deformation is an effective means and development direction for dam safety analysis and evaluation. In this paper, the reliability calculation methods are studied. The basic principles and improved methods of reliability analysis of structures such as the maximum entropy method, the improved first order moment method, the response surface method, the Monte Carlo method and the Rosenblueth method are introduced. The advantages and disadvantages of various methods and their application range are studied. The control integral interval length is proposed. The method of solving equations based on genetic algorithm and matlab fsolve function is used to improve the success rate of maximum entropy method. The purpose of this paper is to put forward a set of risk analysis method for concrete faced rockfill dam and to study the reliability of dam deformation. In this paper, on the basis of academician Chen Zuyu's improved first-order second-moment method, the first-order second-moment method is combined with the numerical calculation program, and the improved first-order second-moment method is introduced into the field of reliability analysis of complex structures. Compared with the commonly used response surface method, this method has the advantages of good convergence, high accuracy and high efficiency. Then, by combining the improved first-order second moment method with Rosenblueth method, a set of methods to evaluate the risk level of concrete faced rockfill dam is proposed. The deformation characteristics of vertical settlement and flexural deformation of the section of a 300m typical concrete face rockfill dam are analyzed and studied. The results show that the parameters of Duncan Zhang E-B model are (?) 0 / RfN / K, (?) / (?) Kbn, (?) _ 0, (?) _ _ _ For the material strength parameter (K) as the tangent modulus test constant and K b as the volume modulus test constant and R f as the failure ratio Kur as the unloading and reloading modulus test constant, the influence on the deformation of the dam body is more complex, and the parameter value, the reference point position, and so on. There is a relationship between the deformation types and the sensitivity of horizontal deformation according to the order of (/) 0, (?) mKb Kur, and the order of sensitivity to the parameters at different positions of vertical settlement is different, and (/) 0 Kb island MRC f is the main factor affecting the vertical deformation. Finally, the sensitivity analysis of the reliability index of settlement deformation of 300m class concrete face rockfill dam and the reliability index of flexural deformation of face slab to the five parameters of (/) 0 ~ (0) ~ (?) K, (?) K _ b are carried out in the last part of this paper. Through analysis and calculation, it is found that the coefficient of variation of Kb, (?) 0 has much greater influence on the reliability index of settlement deformation than the other three factors, while the coefficient of variation of Orogen RF has little effect on the reliability index of subsidence deformation, but the sensitivity of reliability index for flexural deformation of face slab is according to K, (?) 0 / RfN Kb, (?) The variability of K, (?) 0 is the main factor that affects the reliability index of the flexural deformation of the face plate.
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV31;TV641.43

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